The present invention relates to the art of electrochemical machining, and more particularly to the art of aligning electrodes and workpieces during an electrochemical hole drilling operation to form suture needles.
A surgical suture needle must have one end of the suture securely attached to the needle without enlargement of the needle. In the past, suture needles have been provided with an axial hole in the shank end of the needle. Suture needles have been made by drilling and crimping the needle as shown in U.S. Pat. No. 2,620,028. Suture needles have also been made by swaging a maleable metal tube onto a hardened steel tip as illustrated in U.S. Pat. No. 1,591,021. Both of these methods involved ordinary machining processes which are difficult because of the small size of the workpieces.
The problem of drilling a hole along the central axis of a cylindrical member is old and many attempts have been made to provide a mechanical jig which will hold a drill on the central axis. Some U.S. Pat. Nos. disclosing devices of this type are 2,459,013, 1,459,823, 475,664, and 460,883. Again the size of the workpiece makes it difficult to devise a jig which can effectively keep a small workpiece, such as a suture needle and an even smaller drill in coaxial alignment.